aerodynamicist wrote:why 18inch tyre slower than 13inch ?
I'll just address the acceleration part of 'slower.'
As previously posted, the rotational inertia of the wheel and tire varies as the square of the distance of the mass from the axis of rotation. The 18" wheel will have its rim ~1.38 times as far away from the axis or ~1.9 times as much inertia if the mass was the same. But the rim also has more mass because of the larger diameter (by 18/13), so the total increase in inertia is ~2.6 times as much. This increased inertia of the wheels and tires means that more energy must be expended to accelerate them to 60 mph, thus leaving less of the maximum available to accelerate the rest of the car.
Years ago I did a calculation guesstimate of the reduction in 0-60 time for a Mini Cooper S in going from ~ 50lb. stock wheels and tires (!!!) to ~39lb. wheels and tires. With the wheels and tires the same size, the inertia ratio was ~ just linear at 50/39 ~1.28. The guesstimate was an ~.2sec reduction, which is what was achieved on track.
So, with the large number of accelerations in an F1 lap, I'd expect a massive increase in the acceleration time over a lap. (Yes, there will be an offsetting reduction, perhaps, from better cornering.)